Thank you, I will maybe buy solder and learn something new. :+1:
One more question.
How many amps cell do I need for Q8?
Which of these cells would you buy?
Sony Konion US18650VTC5A 2600mAh - 35A button top
Sony Konion US18650VTC6 3120mAh - 30A button top
LG INR18650-HG2 3000mAh - 20A button top
Samsung INR18650-30Q 3000mAh - 15A button top
Sanyo NCR18650GA 3350mAh - 10A Button Top
or any other cell from above link?
Thank you.
The Q8 is a high drain light. It can pull 15 to 16 amps total. So that is 4 amps per cell.
Those are all good. I would go for the ones with a good price.
The Sanyo GA has a chemistry that gives it longer run time and a bit less amp output, so it would probably be last on the list. If you only care about max brightness. If you don’t mind a slightly less max lumens, then the GA will give a bit longer run time.
The Sony VTC6 arrived today. I think the solder blobs should be ok?
Looks great.
Thank you for your kind answer.
+1 … Those are some nice looking solder boobs Spiderlight!!! Impressive……. :+1:
Definitely. I never thought I’d think solder “boobs” (???) were good looking, but those certainly are.
Those look wonderful.
Thank you all for the solder blob compliments.
I’m a bit bored during the Christmas holidays and I’m still waiting for my light thus I tinkered a bit more with the blobs.
I used 800 grid paper to sand the blobs down.
Wrapped some tape around the cells and put them into the tube of my Convoy S2+.
The bigger surface of the tube helps to get a perfectly aligned grinding. Just press with one finger onto the cell and scrape the cell and the tube over the paper.
Now they look more like button top cells.
Just have to wait for my flashlight to arrive now.
Does anyone know the sizes of the o-rings? The bezel and the battery tube please.
All I have is a tape measure. It reads about 2inch/50-51mm and 1.5inch/38mm… Not sure it’s accurate enough.
I just disassembled a second-batch Q8 to measure the grooves and o-rings for you with a caliper. 
The battery tube’s o-ring grooves are approx 47.9mm. The o-rings measures approx 41.0mm when relaxed. Their thickness is approx 1.4mm.
The bezel’s o-ring groove is approx 52.0mm inner diameter. The o-ring measures approx 54.0mm inner diameter when relaxed. Its thickness is approx 1.8mm. Yes, I measured the o-ring as larger than the groove it sits in. 
Are you replacing the o-rings?
Thank you.
I’m not replacing the o-rings.
A member asked if I knew the o-ring sizes. Instead of guessing, thought I’d ask here and share link to thread with them.
In some ways, I miss when this thread was 300 new posts a day, in others less so :smiling_imp:
Q8 still going strong! :+1:
Time for a Q16 thread? 
I still haven’t bought mine. I want cool white. Lol
Found other seller selling BLF Q8. Not sure its original item or not.
Maybe a phony Q8? What is the link?